A typical form of plug-type barrel of thermoplastic material includes a carrier and transportation ring extending around the main body portion of the barrel in the region of the upper end portion thereof. The barrel has at least one plughole connection, for example in the form of a raised rim portion, which is disposed in the edge region of the upper end portion of the barrel and which is disposed within a housing configuration which is let into the upper end portion of the barrel. At its side towards the edge of the barrel the housing is open while at its opposite side it has a boundary wall, from both ends of which extends a respective wall laterally defining the housing, towards the edge of the barrel. The walls defining the housing are delimited at the top side by a transition from the respective wall of the housing into the upper end portion and at the lower side by a transition from the respective wall of the housing into the bottom of that housing. The spacing between the upper transitions of the two side walls of the housing is greater than the spacing between the two lower transitions and the upper transitions diverge in a direction towards the edge of the barrel.
In a barrel of that kind, as is to be found in EP 0 291 695 A2, the arrangement is such that the plughole connection at least partially projects into the interior of the barrel and, at its part which is in the interior of the barrel, it is provided with at least one aperture in order to permit the barrel to be extensively emptied. A disadvantage of that design configuration is that the plughole connection has to be produced separately and mounted to the body of the barrel in a separate working operation. This means that it is not possible to enjoy the advantages of a blow molding procedure which in many cases is used for the production of barrels of plastic material and which permits the barrel to be produced in one piece in a single working operation.